The 19-year-old Cal Poly freshman went missing in 1996
Kristin Smart
Kristin Smart
| Credit: Facebook

The longtime person of interest in the disappearance of Kristin Smart was briefly detained Wednesday morning before being released, multiple outlets report.

Smart, a freshman student at California Polytechnic State University, San Luis Obispo, vanished in 1996 after attending an off-campus party.

Paul Flores, a classmate of Smart’s, was the last known person to see her alive. Flores volunteered to walk the 19-year-old home in her inebriated state from the party, police have said.

According to The Tribune, ABC7 and CBS2, Flores, now 43, was briefly detained but then released. San Luis Obispo County Sheriff’s Office spokesman Tony Cipolla confirmed the news to The Tribune.

Authorities also searched Flores’ home in San Pedro and were seen leaving the home of Flores’ parents in Arroyo Grande with a computer, a brown paper bag, a storage bin and other pieces of evidence, The Tribune reported.

The sheriff’s office did not immediately respond to PEOPLE’s request for comment.

The SLO County Sheriff’s Office said in a press release on Wednesday that it had “served search warrants for specific items of evidence inside four separate locations in California and Washington.”

“Two of those locations are in San Luis Obispo County, one location is in Los Angeles County and one location is in Washington State,” the release stated.

Because the search warrants are “limited in scope and sealed by the court,” the sheriff’s office said that it is “precluded by law from disclosing any further details about them.”

The investigation is still ongoing, the sheriff’s office said.

Kristin Smart
Kristin Smart
| Credit: Facebook

Cipolla told the New York Times, “We would like nothing more than to bring closure to the Smart family in this case.”

In January, the sheriff’s office confirmed that evidence in the case includes two trucks that belonged to family members of Flores at the time, PEOPLE previously reported.

Investigators have collected 140 “new items of evidence” since 2011, in addition to searching nine different locations, serving 18 search warrants, and resubmitting 37 pieces of evidence from the investigation’s early stages for more-current DNA testing and conducted 91 face-to-face interviews, PEOPLE previously reported.